This invention relates to the manufacture of vehicle tires and more particularly relates to the portion of the manufacturing process which subjects the tire to a plurality of quality control tests.
The tire industry has long sought an automated method of improving the quality of tires. Over the years, a variety of tests have been devised for evaluating different parts and different characteristics of tires. In a typical test, a tracking probe picks up data from a designated portion of a rotating tire, and mechanical or electrical apparatus analyzes the data according to a predetermined testing algorithm. The tracking probes may be arranged to obtain data from a variety of different tire surfaces. For example, U.S. Pat. No. 3,303,571 (Veals--Feb. 14, 1967) describes probes arranged to track at several different locations along the sidewall and tread of the tire. Multiple tracking probes are also shown in U.S. Pat. Nos. 2,251,803 (Pummill--Aug. 5, 1941) and U.S. Pat. No. 3,895,518 (Leblond--July 22, 1975).
In recent years, automobile manufacturers have placed increasingly stringent tolerances on tire dimensions and performance characteristics. Meeting all the tolerances normally requires multiple tracking probes and multiple testing algorithms. In order to maintain normal production rates, the multiple tracking and testing algorithms must be completed as rapidly as possible, usually on a single machine in no more than one or two revolutions of the tire. These requirements limit the number of tests which can be performed by existing machines. Unfortunately, the number of tests required has drastically increased, and different tire users typically have different tolerances or performance requirements which necessitate different tests.
Prior art testing machines have been unable to cope with the proliferation of testing requirements. Such testing machines have one or more tracking probes which are dedicated to a specific testing algorithm. There is no convenient and reliable way to mix and match a tracking probe with more than one testing algorithm or vice versa. As a result, it is difficult, if not impossible, for prior art testing machines to readily adapt or modify the tests performed by the machine to accommodate different tolerances or performance requirements of different tire users. Rapid adaptation is essential in order to keep up with production line testing rates.
Accordingly, it is a primay object of the present invention to improve the manufacture of tires by furnishing an automated digital technique for accurately and rapidly matching a predetermined tire tracking probe with a predetermined tire testing algorithm.
Another object is to provide a technique of the foregoing type capable of use by production line personnel.
Still another object is to provide a technique of the foregoing type in which test algorithms or tracking probes can be rapidly and accurately changed to accommodate different tire specifications.
Yet another object is to provide a technique of the foregoing type in which new tracking probes or testing algorithms can be rapidly added without altering existing tracking probes or testing algorithms.
In order to achieve these objectives, the applicant has totally departed from prior art machines which tie a tracking probe to a specified testing algorithm. The applicant has discovered that by using proper digital techniques, including a memory and processor, tracking probes and testing algorithms can be mixed and matched in a rapid and reliable manner according to the test criteria needed to properly evaluate different kinds of tires. Production line personnel can conveniently make the requisite modifications in order to keep up with production line rates of testing. By these techniques, the condition of a tire can be rapidly tested and with a degree of accuracy and reliability previously unobtainable.